The African link

Data being gathered by several radars across the Sahel in support of weather modification may be used in other ways, as proposals for regional data sharing proceed. (Photo courtesy Roelof Bruintjes.)

At a 2005 meeting of the UCAR Board of Trustees in Boulder, Shirley
Malcom was paying close attention to Richard Anthes as the UCAR
president described the organization’s international reach. In front
of the trustees was a map with dots speckling the countries where
NCAR and UOP maintain collaborations, carry out research, or provide
support services. Most continents had at least a few dots—except
for Africa.

“This was only a couple of months after Hurricane Katrina,” says
UCAR trustee Malcom, who oversees education and human resources at
the American Association for the Advancement of Science (AAAS). “I
said, ‘Wait a minute. How can we say that we’re studying
global climate systems when there’s so little UCAR presence
in Africa?’” As Malcom points out, many of the hurricanes
that strike the U.S. Gulf and Atlantic coasts begin as clusters
of thunderstorms crossing the African Sahel. But Malcom was thinking
about more than hurricanes. Her larger point was that UCAR sorely
lacked research, facility, and educational links to an important
part of the globe.

That’s beginning to change, though. Malcom’s query
at the 2005 board meeting served as the catalyst for the UCAR-AAAS
Africa Initiative, which encompasses a wide range of activities.
These include an adaptation of the Weather Research and Forecasting
model (WRF), an upgrade of several radars, and an expansion of
school-based observing through the GLOBE Program.

An initiative is born

After Malcom’s remarks at the board meeting, “nobody
got defensive,” she recalls. Instead, “Rick Anthes began
a conversation about how we might break into this area.” The
committee that resulted chose to leverage and coordinate projects
that already exist instead of trying to launch entirely new efforts.
Its guiding principle is to integrate research and education while
building the capacity for locally based research, with African
rather than American institutions setting the agenda.

Shirley Malcom. (Photo courtesy AAAS.)

Anthes tapped Raj Pandya to coordinate the fledgling initiative.
Since 2004 Pandya has managed the Significant Opportunities in Atmospheric
Research and Science program (SOARS), which provides support and
mentorship for students working toward doctoral degrees in atmospheric
and related sciences.

Because many SOARS protégés are from underrepresented
groups, Pandya is familiar with bridging technological and sociological
divides and forging new communities. In this case, he uncovered a
community that wasn’t aware of its own existence. “We
found there was already a surprisingly large amount of NCAR and UOP
activity involving Africa,” says Pandya, “but only a
few of the participants were aware of each other’s activities.”

Much of the activity thus far has centered on the Sahel, where
the contrast between the moist Guinea coast and the bone-dry
Sahara leads to some of
Africa’s most extreme weather and some of the worst environmental
stresses on vulnerable societies. Hoping to produce more climatic
consistency, several nations in the region have sponsored cloud-seeding
efforts over the last few years, with aircraft and radars acquired
for that purpose. One of the largest players in Sahelian weather
modification is Burkina Faso’s Project SAAGA, which maintains
a King Air turboprop and two C-band weather radars.

Those two radars, plus a third in Mali, can now measure winds
as well as precipitation thanks to low-cost, easy-to-use digital
processors installed in 2006 through a subcontract with NCAR.
The upgrades were completed in time for the African Monsoon Multidisciplinary
Analyses (AMMA), a large international study of wet-season weather
and climate across the Sahel and nearby areas. Although the radars
aren’t
officially part of AMMA, NCAR’s Roelof Bruintjes and colleagues
are working to help make the radar data available to the project’s
scientists, in part by applying distribution strategies in Burkina
Faso that were developed by UOP’s Unidata program to help
American universities acquire and analyze real-time weather data.

Students at the Lycee Nelson Mandela High School in Ouagadougou, Burkina Faso, will be taking regular weather observations with a set of instruments installed in April through the GLOBE Program. At left, Mama Konaté, who represents Mali in the World Meteorological Organization, provides an English translation of the measurement techniques explained in French by Ngosse Fall (center), the GLOBE coordinator for Senegal. At far right is Paul Kucera (NCAR), who assisted in placing the instruments. (Photo by Sherri Heck.)

Bruintjes is also collaborating with the governments of Burkina
Faso and Mali to analyze the results of the rainmaking projects
they sponsor. He’s ­carried out similar studies in a number of other
venues, including Mexico, Wyoming, the United Arab Emirates, and
South Africa. In the Sahel, he says, ­weather modification is
a political hot potato: it’s supported by national governments
but unpopular among some researchers and forecasters. “We’re ­trying
to encourage a rigorous scientific approach and wider use of the
observing infrastructure, while simultaneously being sensitive to
the political decision-making process,” says Bruintjes.

In this case and others, initiative leaders are working closely
with African scientists to learn more about their research interests
and operational needs, rather than providing resources that may
not be required or desired. “We know we have to understand the priorities
from the African point of view,” says Pandya. For example,
the formation of tropical cyclones isn’t a particularly
hot topic for Africans themselves, since the related impacts
occur on the other side of the Atlantic. However, rainfall variations
are of keen interest, especially in the Sahel.

Benjamin Lamptey, an NCAR postdoctoral researcher born and
raised in Ghana, is collaborating with NCAR’s Tom Warner
and

colleagues
on adapting the WRF model to provide the most detailed picture
yet of day-to-day weather in West Africa, particularly around
Ghana. “The
onset and cessation of the rains is the main forecast challenge.
People want to know when there will be a dry spell or wet spell,
even during the rainy season,” says Lamptey. Also important
are dust storms produced by the harmattan, a dry northeasterly wind
that often develops in winter. “The harmattan has implications
not only for air quality and health but also for aviation,” he
says.

Sherri Heck and Ben Lamptey.
(Photo by Carlye Calvin.)

Lamptey completed his doctorate at The Pennyslvania State University
before joining NCAR’s Advanced Study Program in 2005, just
as the Africa Initiative was getting under way. Right off the bat,
he mentioned to colleagues his dream of a top-notch operational model
for West Africa, “but that was just a postdoc talking,” he
says. Later that year, Lamptey gave a presentation to UCAR’s
initiative leaders and mentioned his dream again. This time he found
that support was indeed available for the project from a pool of
seed money ­allocated for the Africa Initiative over the
last two years by Anthes and NCAR director Tim Killeen.

The real-time African
WRF model debuted on the Internet last
fall. Before then, the best operational
models for sub-Saharan Africa featured top resolutions of around
13.5 kilometers. WRF can match that resolution for West Africa
and zoom in to a grid as fine as 4.5 km in the vicinity of
Ghana. This spring Lamptey and colleagues installed a set of
dedicated computers in Boulder to keep the model running 24/7. “We want input
from forecasters in Africa,” says Lamptey. “For example,
they can tell us if the sea breeze is being forecast too deeply
by the model.”

Once Lamptey completes his two-year postdoctoral stint in NCAR’s
Advanced Study Program, he plans to return to Africa and the Ghana
Meteorological Agency in Accra, where he worked before entering graduate
school. Lamptey also plans to work with professors in Ghana to help
establish a full-fledged program in atmospheric science. He connected
with several of his African peers this spring while attending The
Sahel
Conference 2007: Improving Lives by Understanding Weather.
More than 80 participants from 18 nations convened in the Burkina
Faso capital of Ouagadougou during the first week of April.

Aimed at increasing the value and use of local weather data
and models, the conference was cosponsored by Programme SAAGA,
the weather services of Mali and Burkina Faso, and UCAR. The
weather itself bore out the meeting’s theme of atmospheric
impacts, says Lamptey. His flight from Accra was delayed by a
strong harmattan outburst in Ouagadougou; then an unusual squall
line for the time of year blew through during the conference,
bringing light rain and more wind.

The four working groups at the Sahel meeting identified a variety
of desirable steps, including
a memorandum of understanding toward free and open exchange
of radar data in the Sahel and neighboring nations;

an expanded network of radars across West Africa, with subregional
data centers as Internet capacity allows;

strengthening the capability for predicting dust storms;

partnerships and regional strategies for carrying out and
analyzing weather modification efforts; and

a staged approach to improving numerical weather prediction,
with universities and forecast centers collaborating within
each nation and then building international links.

Instruments and students

The Sahel Conference also led to a new node in the worldwide
network of school-based observing sites created through the UOP-based
GLOBE Program. This new weather station is one of about 600 GLOBE
observing sites in 23 African nations. It was installed at the
Lycee Nelson Mandela High School with help from the school’s director, Jean
Pierre Korsaga; NCAR’s Paul Kucera; and Ngosse Fall, the GLOBE
coordinator for Senegal, who conducted onsite training on how to
take weather observations. “The teachers and students were
very excited to be involved in the program,” says Kucera.
He adds that several conference-goers from nearby nations expressed
interest in establishing their own GLOBE sites.

The Sahel Conference took place at the Offices of the Permanent Inter-states Committee for Drought Control in the Sahel (CILSS). (Photo courtesy Raj Pandya.)

Also at the conference was Sherri Heck, a graduate student
at the University of Colorado, who wants to place a different
kind of instrument in Africa. For her doctorate, Heck is analyzing
regional fluxes of carbon dioxide. She’s using the topic as a springboard to bring
science research and education into under-served areas. By working
with local schools, Heck hopes to entrain students while gathering
data that could prove vital to climate research. “If you go
in and take data from a region, I think you should give something
back,” she says.

Heck is applying this philosophy in the United States as well
as Africa. She’s collaborating with Marnie Carroll (Diné College)
to place a CO2 monitoring device atop Roof Butte on Navajo land in
northeast Arizona. Navajo students at Diné will learn how
to operate and maintain the instrument and will have a chance to
create their own CO2-related research project. The instrument, dubbed
the Autonomous Inexpensive Robust CO2 Analyzer (AIRCOA), was developed
by NCAR’s Britt Stephens and colleagues. Components for each
AIRCOA unit cost less than $10,000. The device gathers and relays
CO2 readings every 2.5 minutes, and it can be run autonomously for
months at a time. It will fill a key niche in Arizona, says Heck: “The
southwest United States is poorly represented in terms of carbon
dioxide measurements.”

Scientists also have much to learn about regional CO2 fluxes
in Africa. Heck proposes to site one of the AIRCOA units on an
African mountaintop as part of the Afriflux CO2 monitoring network. “One of the
weakest links in our current understanding of the global carbon cycle
is in Africa, mostly due to a lack of data,” says Heck. At
the Sahel meeting, she met several African scientists who are eager
to help her find a suitable location for AIRCOA. She’ll
also need to find one or more collaborators and a local school
to work with, as well as funding for the instrument itself.

“I’ve struggled almost my whole life to combine my love
of science with my love of helping people,” says Heck. “This
is my attempt to marry the two.”